This section provides background information related to the present disclosure which is not necessarily prior art.
In order to provide comfort for large vehicle operators and reduce driving fatigue experienced by operators of larger vehicles, the operator's cab is suspended utilizing a vibration isolation device and a shock absorption device between the vehicle's chassis and the vehicle's cab which reduces the shock, vibration and consequent pounding the operator experiences during operation of the vehicle. Additionally, the continued application of vibration and shock forces to the cab results in structural damage which ultimately increases the costs associated with maintenance.
The load carried by a large vehicle is supported by the vehicle's frame which is resiliently carried by the vehicle's suspension springs and the vehicle's shock absorbers supported by the vehicle's wheels. Suspension springs typically have a high rate of stiffness which makes the ride more jarring on the operator of the vehicle. To dampen the vibration and shock transmitted to the cab, cab suspension systems have been developed utilizing cab mounting systems that include cab hydraulic shock absorbers and cab air springs to reduce the jounce and rebound movements of the cab with respect to the vehicle's frame.
These cab hydraulic shock absorbers and cab air springs can be mounted at both the front and rear ends of the cab. Typically, a cab is tilted by rotating around a pair of cab air springs and cab hydraulic shock absorbers which are located at the front of the vehicle. The front mounting cab hydraulic shock absorbers and cab air springs often need some type of a bearing to enable the rotational movement during the tilting of the cab. This rotational movement requirement makes it difficult from a design point of view to adequately isolate the cab from the frame.